Can pulling out prevent pregnancy?

"If you're having sex unprotected and he pulls out before he ejaculates, is there still a chance you can get pregnant? If so, what is the risk?"

Stefani, 15, Old Bridge, NJ

That's called withdrawal — and the answer is yes! Anytime you are having unprotected sex, regardless of ejaculation, there is not only a chance of becoming pregnant, but also of getting a sexually transmitted infection.

The reason this can happen is that even though your boyfriend isn't sending in all the troops, that doesn't mean a few overzealous soldiers didn't sneak out and break rank ahead of time. In other words, there can still be some sperm that leaks out before he comes. Besides, the withdrawal method often doesn't work because in the heat of the moment, a guy is just a little reluctant to pull out — and, whoops, it's too late. So even though you and your partner might talk it over a million times beforehand, there's no guarantee his timing will be perfect.

So, if you are going to have sex, always remember your best bet to avoid pregnancy and STDs is to use a condom.